Catalyst slurry for fuel cell membrane electrode and preparation method thereof

Abstract

The invention discloses catalyst slurry for a fuel cell membrane electrode. The catalyst slurry comprises a Pt catalyst, perfluorinated sulfonic acid resin, a solvent and a Pt / carbon nanotube catalyst. The mass of the Pt / carbon nanotube is 1-10% of the mass of the Pt catalyst, the Pt catalyst is a catalyst formed by loading platinum or platinum alloy on carbon particles, and the mass content of platinum is 20-60%; the solvent is a mixed solvent of water and low-boiling-point alcohol, and the low-boiling-point alcohol is selected from at least one of methanol, ethanol, n-propanol or isopropanol. According to the catalyst slurry disclosed by the invention, the CCM is prepared by adopting a slit coating mode and a transfer printing or direct coating mode, a catalyst layer with high platinum loading capacity, no crack and high film thickness consistency can be obtained, and the problems of liquid overflow, cracking, non-uniform thickness of the catalyst layer and the like during coating of the existing slurry are solved.

Description

technical field [0001] The invention belongs to the technical field of fuel cells, and in particular relates to a catalyst slurry for fuel cell membrane electrodes, and in particular, the invention also relates to a preparation method of the catalyst slurry. Background technique [0002] The membrane electrode is the core component of the fuel cell and the place where the electrochemical reaction occurs inside the electrochemistry. It is composed of a gas diffusion layer, a catalytic layer and a proton exchange membrane. The catalyst / proton exchange membrane module prepared by coating the fuel cell catalyst on both sides of the proton exchange membrane, referred to as CCM. At present, the preparation methods of CCM electrodes mainly include transfer printing method and direct coating method, wherein the transfer printing method is to coat the catalytic layer slurry (containing catalyst, perfluorosulfonic acid resin, solvent and additives, etc.) on other base films (such as ...

AI Technical Summary

Problems solved by technology

The slurry viscosity value is too low (<100cP), the intermittent coating process has dripping and casting, and the drying process has the phenomenon that the middle is thick and the sides are thin, resulting in uneven Pt loading, which eventually leads to poor consistency of battery performance

[0004] CN112259753A discloses a method for preparing CCM by directly coating a catalyst slurry on a proton exchange membrane. In this method, the components of the catalyst slurry for CCM include catalyst, perfluorosulfonic acid resin, solvent and additives. The additives contain at least two For compounds or polymers with a nitrogen functional group, the additive ethylenediamine used has a relatively high boiling point. In order to remove the ethylenediamine in the catalytic layer, it needs to be dried at a higher temperature (above 160 ° C). In addition, the excessively high temperature will damage the proton membrane. Thus affecting the performance of the membrane electrode

The preparation process of CCM is cumbersome, adding many uncontrollable factors, which is not conducive to the quality control of industrialized product lines

Images